Physical Sciences 3 Study Guide - Final Guide: Michael Faraday, Experimental Physics, Scandinavian Mountains

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fuchsiamole391

10 Jun 2019

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Document Summary

The magnetic flux of the field the area vector rule. Usually we"ll be interested in the magnetic flux through a loop of wire. A determines the orientation around the edge according to the right-hand. You can change the magnetic flux by changing the area of a loop, changing the magnitude of the magnetic field, or changing the angle between the magnetic field vector and the area vector. Faraday"s law of induction says that a changing magnetic flux will induce an emf in a loop of wire. This induced emf will cause current to flow in the wire. The relationship between flux and emf is: induced d . The minus sign in faraday"s law reminds us that the induced current will create a magnetic field that counteracts the change in flux. One strategy for using lenz"s law is as follows: choose your area vector to point in the same direction as the original field, this way, the flux will be positive.

Related Questions

The long straight wire in figure 6 carries a constant currentofI.
a) What is the magnetic field at a distance (a) from the wire attheborder of the shaded area?
b)what is the magnetic flux through rectangle ABCD?
c) If the current is changing at a rate of dI/dt, find anexpressionfor the change in flux through the rectangle ABCD, interms of Î¼. ,L, a and b, and I.
d)What is the EMF induced around the loop defined by ABCD asaresult of the changing current in part ( c) ?

A coil of wire is connected to a power supply, and a currentruns in the coil. A single loop of wire is located near the coil,with its axis on the same line as the axis of the coil. The radiusof the loop is 2 cm.

At time t1 the magnetic field at the center of the loop, due to thecoil, is 0.4 T, in the direction shown in the diagram; the currentin the coil is constant.

(a) What is the absolute value of the magnetic flux through theloop at time t1?
Î¦ mag = T m2
(b) What approximations or assumptions did you make in calculatingyour answer to part (a)?

Check all that apply.

1.The magnitude of the magnetic field due to the coil is uniformover the area of the loop.
2.The magnetic field outside the loop is zero.
3. The magnetic field due to the coil is uniform in direction overthe area of the loop.

(c) What is the direction of the "curly" electric field inside thewire of the loop at time t1? (Remember that at this time thecurrent in the coil is constant.)
E = 0

At a later time t2, the current in the coil begins todecrease.

(d) Now what is the direction of the "curly" electric field in theloop?
counter-clockwise
At time t2 the rate of change of the magnetic field at the centerof the loop, due to the coil, is -0.36 T/s.
(e) At this time, what is the absolute value of the rate of changeof the magnetic flux through the loop?
|dÎ¦mag/dt| = T m2/s
(f) At this time, what is the absolute value of the emf in theloop?
|emf| = V
(g) What is the magnitude of the electric field at location P,which is inside the wire?
|E| = V/m
(h) Now the wire loop is removed. Everything else remains as it wasat time t2; the magnetic field is still changing at the same rate.What is the magnitude of the electric field at location P?
|E| = V/m